* CDDL HEADER END
*/
/*
- * Copyright 2007 Sun Microsystems, Inc. All rights reserved.
+ * Copyright 2009 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
-#pragma ident "%Z%%M% %I% %E% SMI"
-
#include <sys/refcount.h>
#include <sys/rrwlock.h>
rrw_node_t *prev = NULL;
if (refcount_count(&rrl->rr_linked_rcount) == 0)
- return (NULL);
+ return (B_FALSE);
for (rn = tsd_get(rrw_tsd_key); rn != NULL; rn = rn->rn_next) {
if (rn->rn_rrl == rrl) {
rrw_enter_read(rrwlock_t *rrl, void *tag)
{
mutex_enter(&rrl->rr_lock);
+#if !defined(DEBUG) && defined(_KERNEL)
+ if (!rrl->rr_writer && !rrl->rr_writer_wanted) {
+ rrl->rr_anon_rcount.rc_count++;
+ mutex_exit(&rrl->rr_lock);
+ return;
+ }
+ DTRACE_PROBE(zfs__rrwfastpath__rdmiss);
+#endif
ASSERT(rrl->rr_writer != curthread);
ASSERT(refcount_count(&rrl->rr_anon_rcount) >= 0);
rrw_exit(rrwlock_t *rrl, void *tag)
{
mutex_enter(&rrl->rr_lock);
+#if !defined(DEBUG) && defined(_KERNEL)
+ if (!rrl->rr_writer && rrl->rr_linked_rcount.rc_count == 0) {
+ rrl->rr_anon_rcount.rc_count--;
+ if (rrl->rr_anon_rcount.rc_count == 0)
+ cv_broadcast(&rrl->rr_cv);
+ mutex_exit(&rrl->rr_lock);
+ return;
+ }
+ DTRACE_PROBE(zfs__rrwfastpath__exitmiss);
+#endif
ASSERT(!refcount_is_zero(&rrl->rr_anon_rcount) ||
!refcount_is_zero(&rrl->rr_linked_rcount) ||
rrl->rr_writer != NULL);
if (rrl->rr_writer == NULL) {
- if (rrn_find_and_remove(rrl)) {
- if (refcount_remove(&rrl->rr_linked_rcount, tag) == 0)
- cv_broadcast(&rrl->rr_cv);
-
- } else {
- if (refcount_remove(&rrl->rr_anon_rcount, tag) == 0)
- cv_broadcast(&rrl->rr_cv);
- }
+ int64_t count;
+ if (rrn_find_and_remove(rrl))
+ count = refcount_remove(&rrl->rr_linked_rcount, tag);
+ else
+ count = refcount_remove(&rrl->rr_anon_rcount, tag);
+ if (count == 0)
+ cv_broadcast(&rrl->rr_cv);
} else {
ASSERT(rrl->rr_writer == curthread);
ASSERT(refcount_is_zero(&rrl->rr_anon_rcount) &&